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Indexed by:Journal Papers

Date of Publication:2020-03-10

Journal:CONSTRUCTION AND BUILDING MATERIALS

Included Journals:EI、SCIE

Volume:236

ISSN No.:0950-0618

Key Words:Seawater; Freeze-thaw cycles; Repeated load; Constitutive model; Plastic damage theory

Abstract:Offshore concrete structures in cold climates inevitably experience seawater freeze-thaw cycles, which increase surface scaling and internally damage the concrete, thereby altering the mechanical properties. The constitutive relation and compression damage to the concrete after seawater freeze-thaw cycles are absent from existing studies of structural nonlinearity. Repeated uniaxial compression tests on prism specimens were conducted to investigate the stress-strain and the damage variable of the concrete after 0, 25, 50, 75, 100, and 125 seawater freeze-thaw cycles. Using plastic damage theory and experimental results, we developed a constitutive model of concrete subjected to seawater freeze-thaw cycles, which was input to ABAQUS for numerical simulation. The results showed that the reloading stiffness degradation trend of compression was basically the same for different numbers of freeze-thaw cycles. Compression damage could be calculated by uniform equations after the peak point. The modeling results matched well with the experimental results, indicating that the constitutive model can provide a theoretical basis for nonlinear analysis or design of offshore bridges in cold climates. (C) 2019 Elsevier Ltd. All rights reserved.